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Tim Wescott Tim Wescott is offline
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Default Need odd 12V pwr supply

On Wed, 02 Nov 2011 10:35:54 -0700, Paul Drahn wrote:

On 11/2/2011 8:57 AM, wrote:
Runs from auto power.

Need: regulated 12v, no spikes when vehicle is started
5V, @ 2 amps (USB)
5V, @ 100-200ma, (USB) the 200ma needs to be
absolutely no higher than 200ma under any circumstances

And, this last output needs a timer, that will shut it off for 10 or
so seconds, prefereably a programmable time, 12:00am, or, every 24
hours.

thanks

gary

I think you are posting to the wrong group. You are asking for the
custom design of a switching poser supply. Your 12 volt auto battery
will go to 8-10 volt or lower when turning the starter, then go to over
14.5 when recharging the battery.

Paul


Yup. Easy to design (well, except for the "runs off of auto power and is
glitchless -- but that can be coped with). But possibly hard to find,
particularly with your 200mA current limit (and you should specify what
happens when the load wants more than 200mA -- voltage droop? complete
shutdown forever? shutdown for some period of time, what?).

Basically, if someone hasn't needed it already, then you ain't gonna find
it.

Try sci.electronics.design either for suggestions on how to design, or to
find a designer that can do it for you. Or my website, if you just want
it done.

--
www.wescottdesign.com